The health and safety of athletes during sports is becoming increasingly important with society's increased awareness of the cumulative effects of many minor traumatic brain injuries. Several American college-level football teams have integrated accelerometers into the players' helmets that trigger on large impacts and record the resulting accelerations to provide a way to detect and understand minor traumatic brain injuries in sports. This information is wirelessly transmitted to the sideline for post-game analysis by coaches and research scientists. Although the primary goal of these devices has been to identify impact conditions for the purpose of establishing helmet performance standards, some scientists have proposed that instrumented football helmets could be used to monitor the impact history of professional players.
Outfitting helmets with accelerometers for the purpose of understanding impact conditions and monitoring player exposure has serious drawbacks. As an initial matter, helmet instrumentation cannot measure the actual velocity of a helmet. Football helmets are elastic and restore much of the energy absorbed during the impact. These “elastic” impacts between two helmets cause the helmets to rebound and, as a result, the total changes in velocity measured by the helmet accelerometers are typically higher than the original impact speed. Because helmet performance standards must start with the establishment of the range of impact velocities that players experience, the use of helmet accelerometers is fundamentally flawed. As a further matter, the cost of providing accelerometers in every helmet is generally out of reach for most high schools and many college schools. Due to the inability of accelerometers to measure true impact velocities and the high costs of implementing these systems, this approach is impractical for most organized football leagues.
From the above discussion, it can be appreciated that, in order to provide safe monitoring of all sports players, a new, cost-effective solution for analyzing impacts is needed.